Flexible conductor.



' Patented Aug. 13, 1918 A. PHUESSMAN.

FLEXIBLE CONDUCTOR.

A l APPLICATION FILED OCT. IT 1917.

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UNITED STATES PATENT OFFICE.. ALEERT rEUEssMnN, OE BERWYN, ILLINOIS, ASSIGNOE To WEsTEEN ELECTRIC COM- PANYJNCOEPOEATED, or NEW YORK, N. Y., A coEroEATION OE NEW YORK.

FLEXIBLE CONDUCTOR.

Specification of Letters Iatent.

Patented Aug'. 13, 1918.

Application iled October 17, 1917. Serial No. 197,042.

lTo all lwhom it may concern.-

Be it lmown that I, ALBERT PRUEssMAN, a citizen of the United States, residing at Berwyn, in the county of Cook and State f Illinois, have invented certain new and useful Improvements in Flexible Conductors, oi

which the following is a full, clear, concise, and exact description.

This invention relates to flexible conductors and in particular to exible conductors of the type used in making tinsel cords for connecting telephones in circuit, making connections at telephone switchboards and other similar indoor uses.

The requirements of a satisfactory conductor for telephone cords for use in subscribers stations and in connection with telephone switchboards are that the conductors be iieXible, have a high electrical conductivity and be capable of withstanding severe service conditions for a long period of time.

Flexible conductors having a suitable conductivity have been' obtained by the use of tinsel threads, but the life of 'a cord having such conductors has not been satisfactory, due to the comparatively short period of service which they withstand before opens or partial opens in the conductors are developed, resulting vin the cords becoming noisy and necessitating their removal and I replacement by new cords.

= It is the object of the present invention to produce a conductor which will not onl possessthe qualities of flexibility,- and hig 85 conductivity, but one which will in addition be capable of much longer service than it has been possible to obtain with the type of tinsel conductors used heretofore.

To attain this object, a feature of the invention consists in providing a composite conductor consisting of a plurality of strands, each of which in turn' consists of a plurality Ometal tapes wound in individual layers on a textile cord or thread.

The individual tapes of each strand are' wound in the same direction, theI outer ones 'thereby causing the inner ones to bind closer to the core, and the strands are then twisted i in the reverse direction inorder to produce a composite conductor, which will be iiexible and not subject to twisting or becoming l kinked. By means of this construction 1t 1s possible to use metal tapes rolled so thin as to give the maximum amount of wear when 66 subjected to repeated bending and yet mam- 'ed on core 4 of textile material.

tain high conductivity as a result of the plurality of tapes used. Moreover each wound tape serves as an armoring for all inside tapes and the abrading or cutting of tapes, due to the sliding motion when a conductor is bent, is limited to the outer tapes of each strand. In case of the severing of one of these outer tapes the life of the conductor is not seriously afected, since the open part will be bridged by one or more of the tapes on the same strand. Accordingly it is possible to keep in service a cord employing conductors embodying this invention even though a number of the tapes of the various strands are cut in two, since the open tapes are bridged and do not permit a cord to become noisy.

This invention may be more clearly understood by reference to the accompanying drawing in which the ligure shows a composite conductor of six strands made up in a rope-lay, each strand consisting of a tex.

tile cord, upon which three metal tapes are helically wound in individual layers.

The conductor illustrated in the drawing consists of six individual strands 3 3, twist- Each' strand consists of a textile thread or core 5, .upon which is helically wound a metal tape 6,l preferably of a material having high conductivity. Over the tape 6, and in the same direction, is wound a similar metal tape 7 which acts as an armoring for tape 6, and assists in binding it to the core 5. A third metal tape 8 is next wound about tape 7, and in the same direction as the previous tapes, thereby completing the forming of the strand 3. In order to twist, the direction of lay 0r twist of the revent any y tendency for the conductor to ink or unsol strands making up the complete conductor is opposite to that of the metahtapes wound upon the core 5.

In service these conductors will be subjected to continual bending during which a sliding action takes place between adjacent strands, resulting in the abrading or cutting. of the metal strands. By resorting to thev proposed construction the vcutting action, due fto individual strands sliding over one anotheryis reduced to a minimum, since no cutting action takes place betweenV the tapes of individual strands but only between the outer tapes of the dii'erent strands. vMoreover, the construction is such that when a breaker partial break,occurs, that particular spot is bridged by one or more tapes, and` 1.,A flexible composite electrical conduct tor, comprising a large number of very thinY strands of. conducting material,

and lexible a smaller numberof strands of a non-conducting material with high flexibility and tensile strength, a plurality of such strands of conducting material being wound upon each of said non-conducting strands to form a. composite strand, and the resultant composite strand' being twisted into a rope-lay.

2. A flexible'conductor rality of conducting strands twisted together, each of said strands `comprising a textile core about which are woundv a .p1u-

rality of thin' conducting tapes, said tapes being wound in individual layers and in adirection opposite to the twist ofthe strands In witness whereof, I hereunto subscribe comprising ay plumy name this 13th dayl ofY October, A. D. 25

` i ALBERT rBUE'ssMAN'. 

